The shindig, at The Fillmore in Miami Beach, lured several thousand supporters who wanted to see Heat star sing badly.

James stole the show (video below) with his rendition of Juvenile‘s Back That Ass up — even if Battier and center Greg Oden performed with The Hangover‘s Ken Jeong.

Meanwhile, Palm Beach singer Jimmy Buffett spent $24,000 of his Margaritaville dough to buy a bottle of champagne left over from the Heat’s most recent NBA championship celebration signed by the entire team (gallery above).